What happened
On April 17, 2011, at approximately 10:30 local time, a Robin DR 400-120, registration F-HCOV, was conducting a local flight near Carpentras, France. The aircraft was carrying two passengers when the pilot began navigating the Gorges de la Nesque valley, south of Mont Ventoux. During the flight, the pilot realized that the surrounding terrain was rising more rapidly than anticipated and that the aircraft was no longer flying at a safe altitude relative to the ridgelines.
As the pilot attempted to climb, the aircraft's performance proved insufficient to maintain flight parallel to the increasing elevation of the terrain. Simultaneously, the valley narrowed to a point where a 180-degree turn was no longer possible. The pilot reported intermittent stall warnings and, in an effort to prevent a full stall, prepared for a forced landing. The aircraft struck the tops of trees, which cushioned the impact, and came to rest on the ground at an altitude of 1,030 meters. The aircraft sustained heavy damage, but there were no fatalities.
The investigation
The investigation focused on the pilot's flight path and the aircraft's performance capabilities. The pilot, a military helicopter pilot with a CPL (H) ME and IR rating, had approximately 434 total flight hours, including 25 hours on this specific type. Although the pilot had mountain flying training, this was the first time they had flown through the Gorges de la Nesque in an upstream direction.
Investigators determined that the aircraft's weight was near its maximum allowable takeoff mass. Meteorological conditions at the time of the accident were estimated at 13 °C and were not considered a contributing factor to the event.